Observations on the following breeding birds are reported:
Motabilla alba lugens Breeds may to July on the islands: Are, Kurakake, Matsushima, Futago and Hashirigasaki on Shizugawa Bay coast. Its nest material is the seaweed, Zostera marina L.
Apus pacificus kurodae Breeds on Futago Is. The egg dates are June to July.
N. n. nycticorax Beeds on Kurakake I. together with Larus crassirostris. It Nests at the height not more than 50 cm. from the ground and 30% of the nests were found on the ground.
Larus crassirostris Estimated as thirty thousand, breeding on several islands. Lays eggs from middle April to early June. The chicks often taken by kite.
Cepphus carbo Breeds on Futago Is., laying eggs during May and July.

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1. このエナガの個体数調査は長野県下伊那郡上郷村天滝川河岸段丘崖での1956年2月から1959年8月までの観察である。
2. 個体数及び集合状態の季節的変動について整理した。
3. 個体数の季節的変動は6月中•下旬に最高値を示し,3月下旬に最低価を示した。
4. エナガの特殊な変動として一時に多数個体の急増急減があり,これは群単位で調査地域に対して出入しているからである。
5. 蕃殖期におけるエナガは2年間の記録において全年の最大個体数の30%以下が調査地域で蕃殖した。又蕃殖の成功率は70%前後であった。増加率は約140%と180%を示している。
6. 個体数の季節的変動の型は,1) 1～3月の年間最低値を示しながら変動の少い時期。2) 4～5月の一家族ずつ出現するため急増する時期。3) 6•7月の年間最高値を示す時期。4) 8～12月の全量は年間最高値に及ばないが,10羽代から30羽代の間を急減急増の変動をくりかえす時期から成っている。
7. 個体の集合状態の季節的変動は,1) 2～4月の番を組む時期,2) 5月の家族群をなす時期,3) 6•7月の大合同群を形成している時期,4) 8～10月の中•小合同群をなしている時期。5) 11～1月の冬季群の時期,というようにくりかえされる。この変動は地域的に見ると,番では全地域に個体が散在した状態であり,家族群の行動力がついて来ると,いちじるしく集結して個体の偏在した状態を示す。この偏在は中•小合同群として分解すると共に地域的にも分散の傾向へすすみ,冬季の行動圏を形成するに至る。
8. 集合状態の季節的変動の循環の中で,調査地域内の個体が他の地域とつながりを持っていることがあきらかであり,夏季における大合同群により,より大きな地域とより多くの仲間との生活を経験していることは注目に値する。
9. 調査地域における冬季群はこの約120km²の帯状地帯に,およそ1～2群を含み,全個体数が20羽以下位であるが,他の群が他地域から時々出現する。一方早く分出した群が姿を消すことがあり,内部の代謝が認められる。

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This paper is based on 141 'light-house struck specimens'of Locustella o. ochotensis, sent to the writer from the following 17 light-houses since 1924: Kuriles (Kunashiri), Hokkaido (Erimo, Chikyu, Esan), Aomori (Hiradate, Oma, Shiriya), Akita (Nyudo), Chiba (Nojimazaki), Shizuoka (Omae), Wakayama (Hinomisaki), Shimane (Jizo, Hinomisaki), N. Kiushiu (Eboshi), S. W. Korea (Takeshima, Shichihatsuto) and Formosa (Fukikaku). Other specimen and sight records from Yamagata, Niigata, Saitama, Tokyo, Toyama, and S. Korea were also considered. Chief points are as follows:
1) This less-known species passes Japan chiefly in June and late August to October. 2) The spring migration period (early v-vi) is much shorter than that of the autumn (late viii-xi). The breeding period is short (early vii-mid-viii) and the wintering period is five months (xii-iv). 3) The reason for more records in the autumn than in spring should be the tripled post-breeding population and high ratio of young bird accidentals. 4) Distinctly, the migration is heavier on the Japan Sea side than on the Pacific coast of Honshiu, and suggested three migration courses are: firstly, the well-known Philippine-Formosa-Riu Kiu course; secondly, the newly proposed one of Philippine-Formosa-China coast-S. Korea (across the Yellow Sea)-N. Kiushiu; and thirdly, continental course passing Ryojun (Port Arthar). The second is the chief route of this species. 5) More males (4 out of 5) than females were passing Cape Shiriya in early June (the 8th), which was reversed (6 females out of 7) in middle June (the 16th), and no male was included on the 27th. During this period, the measurements of the gonads of both sexes increased (faster in the males). 6) Three fat classes of amount were identified. In spring specimens, there was excess deposition of fat which is reserved to be used as energy for postmigration breeding. In the autumn, the fat was much less, and was more so in the young birds. 7) Both the rate of gonad development and amount of fat were rather constant among the birds of the same flock, but were different by flocks, irrespective of the advance of the season.

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Local wintering flock of the Brown-eared Bulbul, Hypsipetes amaurotis (Temminck), is a "stationary closed flock", being resident within a certain wintering area without change of the flock members. But, the flock consisted of "opened subflocks", the groups within a main flock, with free interchange of members.
In spring, the wintering flock broke up by moving-out of members and in this season, the moving groups of a local flock may pass and/or temporarily join other local flock, and the latter may leave with the passing flock. This may be determined by coincidence of birds' physiological condition.
Most birds of the wintering flock disappeared at the same time, but a few birds remained over a month. The disappearance of the main flock fairly well coincided with the end of abundant fruits of a tree, and remaining few individuals appeared to have suffered from lack of enough food. Thus, they were observed eating (rather unwillingly) the buds of the leaves of Viburnum awabucki K. Koch.) The flower of Cammellia is a favourite food (both nectar and eating) available until late in the season, but it is not the main food.
The disappearance of the main flock (March 2) coincided with the general increase of temperature to above 15°C. and the remaining few birds disappeared (April 16) with the rise of temperature to over 20°C., when passing flocks were observed most frequently (Fig. 2). This difference in migration temperature might indicate the mixture of northern and relatively southern breeding individuals within a wintering flock.
Marked restlessness in behaviour was observed in spring among birds of a flock. The individuals in such state flatter at random in an excited hovering flight near high branches, with frequent breaks by short perchings. Also, two birds often chased with each other excitedly, but this seemed not to be a courtship flight.

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The pratincole, Glareola pratincola, has been considered as a straggler, only ten records being known during the past 60 years. However, recently it was repeatedly observed in Osaka. In August and early September of 1952, '53 and '54 the author observed its flocks of up to seven birds at the mouth of R. Ichikawa, Himeji City, Hyogo. Its coloration, general structure with large eyes and mouth adapted for aerial catching of insects, detailed habits and behaviour, flight and stomach contents of five birds collected, are given. Its stay on migration is very short; it keeps off from salt water and is more sensitive to tidal conditions than other shore-birds. Its flight is often acrobatic and feeds in the air, and makes a long glide before landing. Entire dragonflies, butterflies (Polytremis), grosshopper, ground beetles and ground bees, etc. were found in the oesophagus and gizzard. Often a few entire insects were packed in the mouth.

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Generally, the Wagtails are non-gregarious. But Motacilla alba is an exception as reported by Schaefer ('56), Mishima ('57) and Kuroda ('58). Here additional observations in spring is reported with notes on its regular roosting flight in the evening.

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